As the magnetic field lines became more and more twisted,
magnetic potential energy built up, similar to how a roller
coaster car at the top of the track builds up gravitational
potential energy, which is then converted to the kinetic energy
of motion as the car zooms downward.

When the magnetic potential energy of the sun finally hit a
certain point, it snapped, releasing that energy in the form of
heat, light and the motion of particles. Plasma on the sun was
heated up to 20 million or 30 million degrees Kelvin (36 million
to 54 million degrees Fahrenheit). Plasma particles were
accelerated along giant loops that traced magnetic field lines
down through successive layers of the sun's atmosphere.

At the same time, some plasma particles from the sun's atmosphere
were accelerated away from the surface, out into space. Such a
release of material is called a
coronal mass ejection. Many of these protons and electrons
made their way to Earth, where they disrupted satellites and
blocked radio communications.

"The holy grail, which is not solved yet, is, what is the actual
trigger mechanism that causes this buildup of energy to be
released?" said Phil Chamberlin, a solar scientist at NASA's
Goddard Space Flight Center in Greenbelt, Md.

However, the Bastille Day solar storm did go a long way toward
helping scientists piece together a general theory of how
eruptions on the sun occur.

"This theory is all based on observations from the Bastille Day
flare," Chamberlin told SPACE.com.

That knowledge will come in especially handy in the coming years,
as the sun ramps up toward a peak in its 11-year cycle of
activity. Near the end of 2013, we are likely to see storms that
rival, or even surpass, the Bastille Day event.

You can follow SPACE.com senior writer Clara Moskowitz
onTwitter @ClaraMoskowitz.Follow
SPACE.com for the latest in space science and exploration news on
Twitter@Spacedotcomand onFacebook.